Field of the Invention
The present invention relates to a lens barrel, an optical apparatus, and a method of manufacturing the lens barrel.
Description of the Related Art
Conventionally, a mechanism for adjusting the position of an optical element, such as a lens included in an optical system, in a direction orthogonal to an optical axis of the optical system has been developed to prevent an optical performance degradation caused when the optical element is decentered off the optical axis due to, for example, manufacturing error. A recent increasing sensitivity of the decentering of a lens unit due to, for example, downsizing of the optical system requires a higher accuracy of the adjustment.
Japanese Patent No. 4,732,714 discloses an optical apparatus in which an optical element is pressed in the direction of an optical axis (optical-axis direction) by a tool, and the position of the optical element is adjusted in a direction orthogonal to the optical axis while the tool is prevented from moving away from the optical element until the optical element is bonded. Japanese Patent Laid-open No. 11-174301 discloses a lens apparatus in which part of a lens holder is exposed outside a lens barrel, and an adjusting force applied to this exposed part from outside the lens barrel adjusts the position of the lens holder in a direction orthogonal to the optical axis.
In the disclosure of Japanese Patent No. 4,732,714, the tool is provided with a presser for pressing the optical element in the optical-axis direction, which complicates the structure of the tool. Moreover, since the invention disclosed in Japanese Patent No. 4,732,714 relates to an adjustment method of a single lens unit, which is not applicable to an adjustment in combination with other barrel components, the lens unit is likely to suffer the decentering when combined with other lens units. In the invention disclosed in Japanese Patent Laid-open No. 11-174301, although a lens unit is adjusted in combination with other barrel components, the lens unit is held by a holding force due to sandwiching, not by any fixer, after the adjustment. The position of the lens unit is likely to be shifted when an external force greater than the holding force is applied to the lens unit.